The invention relates to a tool of a breaking apparatus, such as a percussion hammer or percussion drill, especially for improving the lubrication of the tool.
A conventional impact breaker or breaking apparatus includes a hydraulic or pneumatic percussion hammer which includes a frame formed with a cylinder containing a percussion piston and a sleeve for receiving a proximal or inner end portion of a tool with an end face of the tool presented toward the piston. The proximal end portion of the tool is releasably fitted in the sleeve and is held by one or more retaining pins which allow limited linear movement of the tool relative to the sleeve. The breaking apparatus also includes valving which controls supply of operating fluid to the cylinder for repeatedly driving the piston to strike the tool. The tool also has a distal or outer end portion for engaging material to be broken. The percussion hammer may be embodied in a portable breaking apparatus, such as a hydraulic hand breaker or pneumatic drill, or it may be attached to a power-driven carrier, such as an excavator.
The proximal end portion of a tool used in a conventional breaking apparatus is surrounded by a substantially smooth surface. In order to work advantageously, the joint by which the tool is mounted to the frame requires lubrication between the sleeve and the tool. In order to provide the lubrication between the tool and the sleeve, the latter is at least partly grooved on the surface touching the tool, whereupon it is possible to substantially decrease the running of the lubricant away from the surfaces to be lubricated during the use of the breaking apparatus, and to spread the lubricant more evenly between the different parts of the joint surfaces.
The purpose of the present invention is to eliminate prior art drawbacks and to provide an improved tool of a breaking apparatus which is easier to use and by means of which the lubrication of the joint between the breaking apparatus and the tool is ameliorated.